1. Field of the Invention
This invention relates to a method and apparatus for tape recording and/or reproducing a time code signal together with digital video and audio signals.
2. Description of the Prior Art
In a conventional analog video tape recorder (VTR), for example, as shown in Japanese Patent Publication No. 23993/83, a time code signal, such as, an SMPTE time code, is recorded in a time code track extending longitudinally along a side edge of the magnetic tape, and also in a recording area for the vertical blanking period of each slant track in which the video is recorded. In the reproducing or playback mode, the time code signal is read from the longitudinal time code track along the side edge of the magnetic tape so long as the tape is being driven at an adequate speed, for example, as when the tape is being driven at the normal or standard speed used for recording and playback, or when the tape is being driven at a high tape speed, as in the fast-forward or rewind mode, or at a speed that is slightly reduced relative to the normal tape speed. However, when the tape is being driven at a very slow speed or when the tape is at rest, as in the still reproducing mode, the time code signal is read from the slant tracks. Thus, the time code data can be continuously obtained in the conventional analog video tape recorder without regard to the speed or direction of the tape drive.
In a digital VTR, the digital video signal is shuffled, for example, over 50 lines, before being recorded on the magnetic tape. Therefore, if the time code signal is recorded together with the digital video signal in the slant tracks, for example, as noted above in respect to the conventional analog VTR, it will be difficult to accurately read the time code signal in certain of the tape speed modes employed during playback or reproducing. Therefore, in conventional digital VTRs, the time code signal is recorded only in the time code track extending longitudinally along a side edge of the magnetic tape, and cannot be accurately read during playback in abnormal reproducing modes, such as, the still mode or the very low tape speed mode.